The present invention relates to a radio signal controlled timepiece including a display for indicating the reception of a transmitted signal.
Devices of this type are shown, for example, in German Offenlegungsschrift No. 30 15 312 published Oct. 22, 1981. In the context of the present invention, a radio signal controlled timepiece combines a conventional timepiece having an electronic time keeping circuit with a radio receiver. The radio receiver receives a signal on which the actual time of day is coded. Periodically, the time displayed by the timepiece is compared with the transmitted time. If the displayed time deviates from the actual time, appropriate steps are taken to correct the time displayed on the timepiece.
Particularly when the radio signal controlled timepiece is designed as a consumer item, interference or blocking of the radio signal may result from the positioning of the timepiece or from temporary environmental conditions. Temporary disturbances are not fatal to proper operation of the device, but typically merely cause the decoding of the actual time information and its comparison with the current time display to be delayed from a regularly scheduled point in time to a time when more favorable receiving conditions exist. However, when poor reception is attributable to nontemporary conditions, proper reception will not occur at a later time and correction of improperly set or inaccurate time information will not take place.
There is little practical utility to an everyday user of a consumer timepiece to perform an electronic comparison of inadequately received time decoding information against standard pulses and provide a digital display indicating the quality of the received signal. For example, coded information related to the signal quality could be displayed to indicate whether proper operation is occurring. Though such a digital evaluation of the receiving conditions might be of scientific interest, it provides no particular useful information to a typical daily user of a consumer timepiece.
Accordingly, it is an object of the present invention to provide a radio signal controlled timepiece having a standard time display including an hour hand and a minute hand, and which will generate an indication of the quality of the received coded time information that will be readily interpreted by an everyday user without the necessity of additional display means. More particularly, it is an object of the invention to provide a radio signal controlled timepiece which utilizes a standard clock display to indicate whether or not the coded time information is being properly received, and thus whether or not a correction of a possibly incorrect setting of the hands will occur.